Page 97 of 170

97n
IndexDataTechnologyRepairsCar careControlsOverview
Hardtop6 Remove the two oval cover panels
from the front of the hardtop frame,
using a screwdriver, if necessary
7 Position the tool for locking the
hardtop, and turn it outward until you
hear an audible click. Do this both on
the left and right side of the hardtop
frame to release both catches
8 The hardtop's detent mechanism is
now completely disengaged. With the
aid of an assistant, lift the hardtop up
and over the rear of the vehicle
Do not set the hardtop down
upright, as damage could result.<520de111
9 Place the hardtop on the hardtop
cart as described in the enclosed
assembly instructions 520de162
10 Press the left and right protective
covers onto the hardtop brackets.InstallingGoes the same way as for taking the
hardtop off, just do it in reverse order.
Whenever the hardtop is in constant
use, the fabric convertible top does not
need to be dismantled, even in winter.
Before storing the fabric convertible top
in the convertible top compartment, it
has to be completely dry to keep any
water or mildew stains from forming.
Two individuals are required for
removal and installation. When
removing and installing the top, always
proceed with utmost caution to avoid
damage to the vehicle's paint and
bodywork or to the hardtop itself.520de110
Page 98 of 170

98n
Information for your safetyThe factory has approved steel-belted
radials with emergency driving charac-
teristics for your vehicle. These tires
combine optimal driving safety with the
comfort you desire.
It is not merely the tire's service life, but
also driving comfort and Ð above all else
Ð driving safety that depend on the
condition of the tires and the mainte-
nance of the specified tire pressure.
Incorrect inflation pressure is a frequent
cause of tire damage. It also signifi-
cantly influences the roadholding ability
of your BMW.
Check tire inflation pressures
regularly (refer to page 26), at
least every two weeks and before
beginning a longer trip. If this is not
done, incorrect tire pressures can
cause driving instability and tire
damage, ultimately resulting in acci-
dents.<
Run-flat tiresYour BMW Z8 is equipped with run-flat
tires.
The assembly consists of self-support-
ing tires mounted on specially-designed
wheel rims. Special reinforcement
elements support the sidewalls in the
event of pressure loss. Although tire
performance is then restricted, the
vehicle can still be driven on the
deflated tire for a limited distance. Your
vehicle is equipped with a tire pressure
monitor that signals you in case of a flat
tire.
For further information, refer to
pages 67, 135.
Tire tread Ð tire damageInspect your tires frequently for tread
depth, wear, signs of damage and for
foreign objects lodged in the tread.
Tread depth should not be allowed to
fall below 0.12 in (3 mm), even though
the legally specified minimum tread
depth is only 0.063 in (1.6 mm). At a
tread depth of 0.063 in (1.6 mm), tread
depth indicators (arrow) in the tread-
groove base will indicate that the legally
permissible wear limit has been
reached. Below 0.12 in (3 mm) tread
depth, there is an increased risk of
aquaplaning, even at relatively
moderate speeds and with only small
amounts of water on the road.390de331
Tire inflation pressure Tire condition
Page 99 of 170

99n
IndexDataTechnologyRepairsCar careControlsOverview
Avoid overloading the vehicle so
that the permitted load on the tires
is not exceeded. Overloading can lead
to overheating and increases the rate
at which damage develops inside the
tires. You could have a blowout as a
result.
Unusual vibrations encountered during
normal vehicle operation can indicate
tire failure or some other vehicle defect,
as can variations in normal vehicle
response, such as a pronounced
tendency to pull to the left or right.
Should this occur, respond by immedi-
ately reducing your speed. Proceed
carefully to the nearest BMW center or
professional tire center, or have the
vehicle towed in to have it and its tires
inspected.
Tire damage can endanger the lives of
both the vehicle occupants and other
road users.<
To maintain good handling and vehicle
response, use only tires of a single tread
configuration from a single manufac-
turer. BMW tests and approves wheel/
tire combinations. Refer to page 103.DOT Quality GradesTread wear
Traction AA A B C
Temperature A B C
All passenger vehicle tires
must conform to Federal Safety
Requirements in addition to these
grades.
rating based on the wear rate of the tire
when tested under controlled condi-
tions on a specified government test
course.
For example, a tire graded 150 would
wear one and one-half (1g) times as
well on the government course as a tire
graded 100. The relative performance
of tires depends upon the actual condi-
tions of their use, however, and may
depart significantly from the norm due
to variations in driving habits, service
practices and differences in road char-
acteristics and climate.
TractionThe traction grades, from highest to
lowest, are AA, A, B and C.
Those grades represent the tire's ability
to stop on wet pavement as measured
under controlled conditions on speci-
fied government test surfaces of
asphalt and concrete. A tire marked C
may have poor traction performance.
The traction grade assigned to
this tire is based on straight-
ahead braking traction tests, and does
not include acceleration, cornering,
aquaplaning, or peak traction charac-
teristics.<
Tire condition Tire replacement
Page 100 of 170

100n
Tire replacement Tire rotation TemperatureThe temperature grades are A (the
highest), B and C, representing the
tire's resistance to the generation of
heat and its ability to dissipate heat
when tested under controlled condi-
tions on a specified indoor laboratory
test wheel.
Sustained high temperature can cause
the tire material to degenerate and
reduce tire life, and excessive tempera-
ture can lead to sudden tire failure. The
Grade C corresponds to a level of
performance which all passenger
vehicle tires must meet under the
Federal Motor Vehicle Safety Standard
No. 109. Grades B and A represent
higher levels of performance on the
laboratory test wheel than the minimum
required by law.
The temperature grade for this
tire is established for a tire that is
properly inflated and not overloaded.
Excessive speed, underinflation, or
excessive loading, either separately or
in combination, can cause heat buildup
and possibly a flat tire.<
Uniform Tire Quality GradingQuality grades can be found where
applicable on the tire sidewall between
tread shoulder and maximum section
width. For example:
Tread wear 200 Traction AA
Temperature A
Use only tires with emergency
driving characteristics as there is
no spare tire available if you get a flat
tire. For further information, refer to
page 135.
factured is indicated by the code on the
sidewall:
DOT ... 1200 indicates that the tire was
manufactured in week 12 of 2000.
Although tires may have a theoretical
service life of up to 10 years, BMW
strongly recommends that you replace
all tires after an absolute maximum of
6 years.
Between the axles
If different tire sizes are mounted
on the front and rear axles (refer to
page 103), then the tires may not be
rotated from one axle to the other.<
The tread wear patterns at the front end
differ from those at the rear Ð the actual
patterns will vary according to indi-
vidual driving conditions. In the inter-
ests of safety and maintaining optimal
handling characteristics, tire rotation is
not recommended.
Page 101 of 170

101n
IndexDataTechnologyRepairsCar careControlsOverview
Wheel and tire combinations The right choice
Use only wheels and tires
approved by BMW for the corre-
sponding vehicle model, as otherwise
the tires may make contact with the
body as the result of tolerances despite
the same nominal size being used,
resulting in serious accidents. If non-
approved wheels and tires are used,
BMW cannot evaluate their suitability,
and therefore cannot be held liable for
driving safety.<
For wheel and tire specifications
approved by BMW, refer to page 103.
The correct wheel-tire combina-
tion affects different systems that
otherwise will not function properly,
e.g. ABS, DSC and RDW.
For this reason, use only tires of the
same brand and tread pattern on the
vehicle and, for example, restore the
approved wheel-tire combination
following a flat tire as soon as
possible.<
Codes on tires and wheels The code on tires has the following
meaning.
Codes on radial tires:
The speed rating indicates the approved
maximum speed for the tire.
Summer tires:
S = up to 112 mph (180 km/h)
T = up to 118 mph (190 km/h)
H = up to 130 mph (210 km/h)
V = up to 150 mph (240 km/h)
W = up to 167 mph (270 km/h)
Y = up to 186 mph (300 km/h)
ZR = over 150 mph (240 km/h) For example:
Nominal width
in mm
Aspect ratio in X
Radial tire code
Rim diameter in inches
Load rating
(not on ZR tires)
Speed rating
(before R on ZR tires)
245/45 R 18 96 W
Winter tires:
Q M+S = up to 100 mph (160 km/h)
T M+S = up to 118 mph (190 km/h)
H M+S = up to 130 mph (210 km/h)
Codes on light-alloy wheels:
Protect tire valves from dirt by using
screw-on valve stem caps. Dirt in the
valves frequently leads to slow leaks.
Tires with emergency driving character-
istics also possess an additional identi-
fication mark that varies by manufac-
turer, e. g.:
Bridgestone RFT
Dunlop DSST
Goodyear EMT
Michelin ZPStorage Store tires in a cool, dry place,
protecting them against light when-
ever possible. Protect the tires against
contact with oil, grease and fuel. For example:
Rim width
in inches
Code letter for
flange type
Symbol for full-drop
center rim
Rim diameter in inches
Hump on the 2 rim shoulders
8x18EH 2
J
Page 102 of 170

102n
Special features of winter tires Snow chains
*
Choosing the right tireFor winter road driving, BMW recom-
mends winter tires (M+S radial belt
tires). Although all-season M+S tires
provide better winter traction than stan-
dard summer tires with H, V, W and ZR
speed ratings, they generally fail to
provide the same levels of performance
as standard snow tires in winter driving.
In the interests of safe tracking and
steering response, install radial tires
made by the same manufacturer and
with the same tread configuration on all
four wheels if you elect to mount winter
tires.
Use only winter tires with emer-
gency driving characteristics as
there is no spare tire available if you get
a flat tire.
For further information, refer to
page 135.<
Do not exceed specified
maximum speeds
Never exceed the maximum speed
for which winter tires are rated.
Unprofessional attempts by laymen to
service tires can lead to damage and
accidents.
Have this work performed by skilled
professionals only. Your BMW center
will be glad to assist you with both their
expertise and the proper equipment for
your vehicle.<
Tire condition, tire pressureOnce the tread depth on winter tires is
less than 0.16 in (4 mm), they are no
longer suitable for winter road driving,
and in the interest of safety should be
replaced.
Comply with the specified tire inflation
pressures Ð and be sure to have the
wheel and tire assemblies balanced
every time you change the tires.
The use of narrow-link BMW snow
chains is permissible in pairs only on
the rear wheels with winter tires with
tire size 245/45 R 18 96 H. Comply with
all manufacturer's safety precautions
when mounting the chains.
Do not activate the RDW system
while using snow chains.
Malfunction warnings and undetected
losses in pressure are possible when
driving with snow chains.
For further information, refer to
page 67.<
Page 103 of 170

103n
IndexDataTechnologyRepairsCar careControlsOverview
Approved wheel and tire specifications Snow chains
*
It is impossible to install snow chains
when using summer tires
275/40 R 18 99 W.
Do not activate the RDW system
while using snow chains.
Malfunction warnings and undetected
losses in pressure are possible when
driving with snow chains.
For further information, refer to
page 67.< BMW tests certain tire brands for each tire size, classifies them as road-safe and
approves them. Your BMW center can provide further information.
Observe any regulations applicable in the country of use, e.g. requiring entry in
the vehicle documents.
Tire specifications Light-alloy wheel
BMW Z8
Summer tires
Front: 245/45 R 18 96 W 8Jx18EH2
Rear: 275/40 R 18 99 W 9Jx18EH2
Winter tires
245/45 R 18 96 H M+S 8Jx18EH2
The use of rims and wheel bolts
that do not meet the specifications
of the original factory-installed equip-
ment will affect the safe operation of
your vehicle and may cause an accident
and personal injury.
Never mix tires of different design, such
as steel-belted radials with radial bias
belted or bias-ply tires, etc. Mixing tire
types will adversely affect roadholding
and can lead to loss of vehicle control.<
Page 104 of 170
104n
Never attempt to carry out service
or repair operations on your
vehicle if you do not have the required
technical background. Always switch
off the engine and allow it to cool down
before working in the engine compart-
ment. Always disconnect the battery
before working on any electrical
systems or equipment, especially when
these are located within the engine
compartment. Comply with all appli-
cable instructions and safety precau-
tions. Failure to work in an informed,
professional manner when servicing
components and materials constitutes
a safety hazard for vehicle occupants
and other road users. If you are not
familiar with official servicing proce-
dures, please have the work performed
by your BMW center.<
To release
Pull the lever located under the left-
hand side of the instrument panel. 520de084
To open
Press the release handle upward and
open the hood.520de153
Hood